One of the main reasons for the rapid change and growth in computer power requirements is the increase in volume of data processed, stored, transmitted, and displayed. As a result, power requirements have grown very rapidly over the last few years. To control the increase in power dissipation due to increased frequency and gate count, operating voltages have been reduced, since power scales as the square of voltage but scales linearly with respect to the frequency. The increasing frequency demand forces the voltages down proportionally in order to maintain a reasonable level of power dissipation. Today, feeding this large amount of “ultraclean” current at low voltages with huge transient response capability has become a key technology driver of power management in computer systems.
Such power supply concerns assume particular significance in advanced memory designs currently being implemented. Additionally, rising bus and processing speeds are also demanding newer memory architectures that deliver improved performance by increasing clock frequencies and available bandwidth. However, due to such ever-increasing performance requirements, issues of power consumption and dissipation have become even more critical in the field of computer system design.
It is well-known that a computer system's memory can account for a significant portion of the computer system's total power consumption. Since the amount of power consumed by the memory can be quite variable and unpredictable depending on transactional throughput, current designs are typically overprovisioned in terms of power supply, cooling, line power, and the like, so as to maximize the potential power dissipation. Such overprovisioning is not only inefficient in terms of cost, but operates as a significant design constraint on the system memory density.